Octans the Octant-Southern
Hemisphere
The
constellation that contains the South Pole star, despite this
privileged position, Octans is faint and unremarkable. There is no
southern equivalent of Polaris, the North Pole star. The nearest star
to the south celestial pole is Sigma Octantis with
a magnitude
of only 5.5 which lies about 1 degree
from the pole.
The
constellation of Octans commemorates the instrument known as the
Octant, a forerunner of the sextant, invented by the English
astronomer John Hadley and used by him for measuring star positions.
The
constellation was introduced by Nicolas Lacaille during his stay at
the Cape of Good Hope and its dullness is a memorial to his dreadful
lack of imagination.
The
brightest star is Nu an orange K1 class giant star with a brightness
of magnitude of 3.7 lying at a distance of 64 light years.
Sigma
the South Pole Star shines with a brightness of magnitude 5.5 and
lies at a distance of 281 light years. Sigma is a FO giant star with
a temperature of 7,200’C.
No comments:
Post a Comment